Clamp for plate glass racks



April 25, 1933. J. F. JOHNSON 1,905,905

CLAMP FOR PLATE GLASS RACKS Filed April 26, 1930 2 Sheets-Sheet l riaINVENTOR April 25, 1933. J. F. JOHNSON 1,905,905

CLAMP FOR PLATE GLASS RACKS Filed April 26, 1950 2 Sheets-Sheet 2INVENTOR Patented Apr. 25, 1933 UNITED STATES PATENT o rlca JOHN F.JOHNSON, 0F IBELLEVUE, PENNSYLVANIA, ASSIGINOB T0 PITTSBURGH PLATE GLASSCOMPANY, A CORPORATION OF PENNSYLVANIA CLAMP FOR PLATE eLAss aAcKswApplication filed April as,

The invention relates to a clamp or holder for a plate glass rackdesigned to secure the glass against movement on the rack when the rackis being moved from one position to another. The invention has for itsprincipal objects, the provision of an improved clamp of simpleconstruction, which can be easily applied and released, which holds theglass securely at all times, and which will hold a stack of glassregardless of the number of sheets in the stack. One embodiment of theinvention is shown in the accompanying drawings, wherein:

Figure l is an end elevation of a plate glass rack equipped with theimproved clamps. Fig. 2 is a section on the line II II of Fig. 1. Fig. 3is a side elevation of the rack. Fig. 4 is an enlarged detail viewshowing the pawl and ratchet adjustment of the clamping arm. And Fig. 5is a detail showing in side elevation the means for holding the pawl inunlockingposition.

\ The rack itself is of ordinary construction comprising a base 1 onwhich are mounted the inclined uprights 2, 2 carrying the transversestrips 3, 3. The rack is provided just above the base with a pair ofshoulders 4., 4, upon which the edges of the glass sheets 5 aresupported. The stack of sheets 5 rest against the inclined side faces ofthe rack, as indicated in Fig. l and are in no danger of being displacedas long as the rack remains stationary. When it is moved from place toplace, however, by means of an overhead crane, it becomes necessary toprovide means for holding each stack of sheets in position and theapplicants clamp or holder is designed to meet this requirement. Twoclamps are shown, one for each set of sheets, but it will be understoodthat the two constructions are the same so that a: description of onewill be sufiicient. The support for the clamp comprises the brackets 6,6 secured to the end members 2, 2 by means of the bolts 7, such bracketsserving as a support for the horizontal shaft 8 which carries the twoclamps. Mounted for rotation on the end of the shaft 8 is the block 9and swivelled in this block is the end portion 10 of the clamping arm,such clamping arm 1939. SerialNo. A l-7,752.

comprising a portion 11' which extends laterally from the portion 10,and a portion 12 which extends at right angles to the portion 11.Mounted loosely for rocking movement upon the "end of the portion 12 isa plate 13, such plate carrying on its front. face a felt sheet 14 forengaging the face of the outer sheet of glass.

- In order to hold the end lO in its various positions of adjustment, apawl and ratchet is provided, as indicated in detail in Figs. 4. and 5.The ratchet 15 is secured to the end 10 and is engaged by a pawl 16pivoted at 17 and held normally in engagement with the teeth of theratchet by means of the spring 18. The pawlisprovided with a handle 19bymeans of'which it may be swungto release position. It is held inrelease position by means of the detent 2O yieldingly pressed upward bymeans of the spring 21 and adapted to engage: a recess 22 in: the lowerside of the handle 19 when. the handle is swung to release position. Thedetent also serves to prevent the pawl from moving from ope'rativeposition, as will'be seen by reference to Fig.5. This pawl and ratchet.

adjustment permits the clamp to be adjusted tohold stacks 'of glasssheets of different thicknessup to the capacity of the rack.

The clamp is shown in operative position in full lines in the drawingsand at such time the glass sheets are securely held in position againstthe inclined face of the rack. When it is desired to release the clamp,the arm 12 is swung upward around the horizontal shaft 8, the arc ofswing being shown in Fig. 3. The device when thus moved from operativeposition reaches the dotted line positionmarked A in Figs. 1 and 2, atwhich time it lies at the end of the rack and out of the way, so that itdoes not interfere with the removal of the glass from the rack or theplacing of the glass upon the rack. When in operative position, there isno tendency of the device to become disengaged, since the force ofgravity tends to move the plate 13 downward, but such downward movementcan not occur because of the inclination of the sheets 5 so that theclamp tends to tighten rather than to release. The device is thus safeand positive in its holding action, but at the same time can be quicklyand easily released and when in release position is entirely out of theway.

lVhat I claim is:

1. The combination With a rack for carrying plate glass sheets havingone side inclined to the vertical, of a clamp or holder for glass sheetscarried by the rack and resting against said side, comprising a bracketsecured to one end of the rack, a block pivoted on the bracket formovement about a horizontal axis, an arm mounted on the block foradjustment about a Vertical axis, said arm comprising a part extendingsubstantially at right angles to said Vertical axis and a second partextending atsubstantially rightangles to the first part, a plate forengaging the glass mounted for rocking movement on the end of saidsecond part, and means for releasably holding the arm in its variouspositions of adjustment about said vertical axis.

2. The combination with a rack for carrying plate glass sheets havingone side inclined to the vertical, of a clamp 0r holder for glass sheetscarried by the rack and resting against said side, comprising a bracketsecured to one end of the rack, a block pivoted on the bracket formovement about a horizontal axis, an arm mounted on the,

block for adjustmentahout a vertical axis, said arm comprising a partextending substantially at right angles to said vertical axis and asecond part extending at sub stantially right angles to the first part,a plate for engaging the glass mounted for rocking movement on the endof said second== part, and means for releasably'holding the arm in itsvarious positions of adjustment about said vertical axis, said meanscomprising a pawl and ratchet.

In testimony whereof, I have hereunto subscribed my name this 21st dayof March, 1930. Y JNO. F. JOHNSON.

